1. Field of the Invention
The present invention relates to an administrator interface for a data base in a distributed data processing environment. It applies in particular to the supervision of the operation of a data base and to the detection of potential abnormal operations.
2. Description of Related Art
The current trend in the development of data processing systems is to form such a system by associating a plurality of machines or platforms connected to one another by means of a network, (LAN) for example a local area network. In the LAN, any user can run applications of extremely varied types on this group of machines. These applications call services which supply information required to handle the problem or problems they are working on, which are offered by all or some of these machines. A system of this type is called, in the most general designation a "distributed data processing environment", which one skilled in the art usually called a "site".
Each machine or platform is also called a "node" by one skilled in the art, and any process running on any of these machines is designated by the server name, and thus executes a given job on the server.
A data base may be defined as being an integrated data set which models a given environment. The data used by various applications is collected in the same base in order to avoid the problem of their duplication. A conceptual schema associated with a data base describes the structure and the type of data it contains and the constraints which must always be satisfied, the latter function being fulfilled by the data base administrator.
The structure of a data base is composed of a set of files which constitute the physical data storage medium. Three types of files are distinguished. The Data files ensure the storage of the objects created by the users of the base as well as those necessary to the operation of the base. The Redo Log files contain the most recent modifications of the data; they are used to return the data base to a consistent state, without losing the unsaved updates in the data files in case of a hardware or software failure. The Control files contain the information related to the structure of the data base, such as the name of the data base, the name and location of the Data files and Redo Log files, etc., and are updated each time a Data file or Redo Log file is created or renamed.
One of the most widely used data base management systems is the Relational Data Base Management System, often designated by its acronym RDBMS, known under the registered trademark ORACLE V7, produced by the company ORACLE Corp., which uses the standardized language SQL (Structured Query Language) and operates on a machine running the UNIX (trademark registered to Norrell, Inc.) operating system, the communication protocol used being the standardized protocol SQL*NET.
The internal architecture of ORACLE is organized into three levels. A first level, called a file level, corresponds to the structure of the data base and to the way in which the data is stored. A second level, called a storage level, corresponds to the organization of data in main storage; it is composed of a set of buffer areas allocated by ORACLE for containing the data and certain control information. Finally, a third level, called a process level, corresponds to the various Oracle processes which ensure the management of the data (as distinguished from the user-provided processes which ensure the execution of the applications submitted to ORACLE, and the DBMS processes which ensure the management of the data, for example data writing, checkpoint data writing, copying into archive files, etc.). A process is a mechanism of the operating system which makes it possible to execute a series of calculation and input/output operations. The role of the various ORACLE processes is to execute the actions entered by the applications and to exchange the data between auxiliary storage and main storage. The combination of the allocated storage areas and the processes constitutes an ORACLE instance. The latter can also be defined as a set of servers and associated storage spaces which ensures the access to and the integrity of the ORACLE data base. The machines and software programs which run on them and which operate with the ORACLE system are called objects.
Within the scope of the invention, it is assumed that this data base is used in a distributed data processing environment.
In terms of satisfying the constraints mentioned above, the management of the data has three roles of an organizational and technical order. First, it defines the users of the data base, giving each of them a name, a password and a set of privileges or rights to access the data. It also defines the administrator or administrators, who are the authorized persons responsible for it, either in part or in its entirety. Its second role is to assign the definition of the conceptual schema of this base to the administrator, or to have the administrator participate in its definition. The administrator therefore defines the schemas of the various tables and the rules related to these tables.